Western hummingbirds making their way to the Valley

OUTDOORS

Rufous hummingbirds have been spotted in Northampton County

A male Rufous hummingbird sits in the hand of Dorothy Wiltraut of Whitehall.… (COURTESY OF Scott Weidensaul,…)

November 21, 2011|By Gary R. Blockus, Of The Morning Call

The buzz — literally and figuratively — began in mid-October.

Rufous hummingbirds had been spotted in the Lehigh Valley.

The tiny hummingbirds — different than the ruby-throated hummingbirds, Pennsylvania's most common — began showing up at plants, flowers and feeders in Northampton County.

Rufous hummingbirds have been identified in Pen Argyl in September and November, in a backyard garden in Little Gap in October, and several at Jacobsburg State Park this month.

"Between 1995 and 2001, there were four records of Rufous hummingbirds in the Lehigh Valley according to the Lehigh Valley Audubon Society records," said Rick Wiltraut, the environmental education specialist at Jacobsburg State Park, who sighted and identified two near the Jacobsburg Environmental Education Center earlier this month. "This year seems to be an exceptional year."

The Rufous hummingbirds breed in the Pacific Northwest, as far north as Alaska, and migrate to the Gulf of Mexico for wintering, according to Scott Weidensaul, a federally licensed hummingbird bander from Schuylkill County who has authored several bird books.

"All the western species of hummingbird show up from time to time in the East," he said. "By banding them, we are able to track their movements and get a better idea on what they're doing and why."

So far, there have been about five Rufous sightings in the Lehigh Valley, and two have been trapped by Weidensaul, including one that had already been banded.

Weidensaul has banded in the neighborhood of 110-115 hummingbirds over the last 10 years in order to research the migration routes. The Nov. 14 Jacobsburg State Park Rufous trapping provided a first for him, however. Trapping the bird with Wiltraut, Weidensaul captured his first hummingbird that had already been banded.

"This bird was banded on Jan. 9, 2011, in River Ridge, Louisiana," Weidensaul said. "It was an immature male when he was captured by Nancy Newfield, a legendary hummingbird bander who kind of invented the study of wintering hummingbirds. In the 1970s, she noticed more and more western hummingbirds were turning up in Louisiana."

At the time, other scientists thought the birds were lost and would freeze to death in the "brutally cold winters of Louisiana," Weidensaul said with a sly laugh. It has been found since that Rufous hummingbirds can survive in temperatures well below zero.

"It represents only the second foreign-captured Rufous hummingbird in Pennsylvania," explained Wiltraut, who nicknamed the bird "Rufus Jacobsburg." Wiltraut identified a Rufous hummingbird in his Nazareth backyard back in 2001. This year marks the first time a Rufous has been sighted at Jacobsburg.

20 sightings in Pa.

Weidensaul also captured and banded a female Rufous in Pen Argyl on Nov. 11. He said that about 20 Rufous hummingbirds have been sighted in Pennsylvania this fall.

So, if the migration of the Rufous hummingbirds is from the Pacific Northwest to the Gulf of Mexico, why are they continuing to show up in Pennsylvania from October through November, and seemingly in larger numbers?

"There's not a whole lot of banding data yet," Weidensaul said, "but so far, it looks like there's a circular range through the mid-Atlantic to the Southeast and into the Gulf, and then a more direct route back to the Northwest to breed."

But that's only one theory.

Another theory, he said, is that the birds are hard-wired genetically to migrate to the Gulf of Mexico, but every once in a while, there's a genetic anomaly. The mutation causes some birds to fly due west into the Pacific, and they basically die off.

Others have a mutation that causes them to fly eastward and end up in places such as the Lehigh Valley. After a few years of finding their way to the Gulf via the eastern route and breeding, that genetic mutation becomes a regular part of the DNA.

The changing landscape of the United States, from a fully forested native landscape to one that was environmentally ravaged first by the timber industry, then subsequently by the transportation industry, the energy industry and urban development, has also changed the composition of plant and tree life. Plus, this region was considerably colder even at the turn of the 20th century, which may have made this area an undesirable flyover.

"As it starts to get seriously cold, they will migrate to the South," Weidensaul said. "In the Southeast, Florida and other Gulf states into Mexico are like the land flowing with milk and honey in the wintertime. There are lots of flowers, nectar and insects. About 60-70 percent of the hummingbird's diet is insects."

Still at Jacobsburg

Wiltraut and Weidensaul were thrilled to capture a Rufous hummingbird at the feeder on the office building at Jacobsburg State Park. They set up the cage, and within minutes, the Rufous was trapped.